Concentration Dependence of KIE Phosphoenolpyruvate Carboxylase

There are several interesting aspects to this study. The dependence on bicarbonate concentration can be described formally by introducing Equation 11.42 into Equation 11.41 and assuming that only the reaction specified by rate constant k5 is isotope sensitive  

The solution of Equation 11.77 for all unknowns yields 1.013, 0.994, and 0.06 for the intrinsic IE s of 18ks and 18ki, and k3k5/k2k4 [mM], respectively. 

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